The field of the invention is dispensers for chemical concentrates, and particularly the dispensing of chemical concentrates at multiple flow rates and different concentrations.
Dispensers of the type concerned with in this invention are disclosed in U.S. Pat. Nos. 5,320,288 and 5,372,310. While the spraying apparatus disclosed in these patents can control the flow of carrier fluid and chemical product, it cannot do so in a precise and controlled manner.
U.S. Pat. No. 2,719,704 discloses a valve element 31 with eductor passages 41 and 43. These interconnect with inlet openings 58 and 61.
U.S. Pat. Nos. 2,991,939 and 4,901,923 disclose eductor type dispensers having rotatable discs with various sized apertures for controlling the amount of concentrate being drawn into the water flowing through a nozzle.
A dispenser which dispenses chemical concentrate should have the capability of dispensing the concentration at a low rate such as in the instance where a bottle is to be filled and at a high rate where a bucket is to be filled. In the instance of a bucket fill, it is desirable if both a low and high concentration of chemical concentrate can be provided.
The prior art provides either a rotatable eductor with concentrate flow passages, eductor type dispensers having rotatable discs with various sized apertures, or a sliding open-venturi. It does not provide a dispensing apparatus with both sliding and rotating eductors as well as valving so as to afford different concentrations of chemical concentrate at different flow rates.